A single parathyroid hormone level obtained 4 hours after total thyroidectomy predicts the need for postoperative calcium supplementation.

BACKGROUND: Parathyroid hormone (PTH) levels after total thyroidectomy have been shown to predict the development of symptomatic hypocalcemia and the need for calcium supplementation. This study aimed to determine whether a PTH level drawn 4 hours postoperatively is as effective as a level drawn on postoperative day 1 (POD1) in predicting this need. STUDY DESIGN: This is a single-institution retrospective review of 4-hour and POD1 PTH levels in patients who underwent total thyroidectomy from January 2012 to September 2012. If POD1 PTH was ≥10 pg/mL, patients did not routinely receive supplementation; if PTH was <10 pg/mL, patients received oral calcium with or without calcitriol. RESULTS: Of 77 patients, 20 (26%) had a 4-hour PTH <10 pg/mL; 18 (90%) of these patients had a POD1 PTH <10 pg/mL. No patient with a 4-hour PTH ≥10 pg/mL had a POD1 PTH <10 pg/mL. All 18 patients with POD1 PTH <10 pg/mL received calcium supplementation. Three additional patients received supplementation due to reported symptoms or surgeon preference. A 4-hour PTH ≥10 pg/mL compared with a POD1 PTH had a similar ability to predict which patients would not need calcium supplementation; sensitivity was 98% vs 98%, specificity was 90% vs 86%, and and negative predictive value was 95% vs 95%. Of 21 patients who received supplementation, 13 (62%) also received calcitriol, including 9 patients (69%) with a 4-hour PTH <6 pg/mL. CONCLUSIONS: A single PTH level obtained 4 hours after total thyroidectomy that is ≥10 pg/mL accurately identifies patients who do not need calcium supplementation or additional monitoring of serum calcium levels. Same-day discharge, if deemed safe, can be accomplished with or without calcium supplementation based on the 4-hour PTH level. Greater consideration should be given to calcitriol supplementation in patients with a 4-hour PTH <6 pg/mL.

Effect of prophylactic central compartment neck dissection on serum thyroglobulin and recommendations for adjuvant radioactive iodine in patients with differentiated thyroid cancer.

BACKGROUND: Controversy exists in the management of patients with differentiated thyroid cancer (DTC). The purpose of this study was to examine the effect of prophylactic central compartment neck dissection (CCND) on serum thyroglobulin (Tg) levels and recommendations for adjuvant radioactive iodine (RAI). METHODS: The records of 103 patients who underwent completion/total thyroidectomy for DTC between January 2009 and November 2010 were reviewed. Prophylactic CCND was defined as removal of central compartment lymph nodes with no preoperative or intraoperative evidence of lymphadenopathy. Institutional protocol included a diagnostic whole-body scan before RAI; patients with a negative scan and Tg < 2.0 did not receive adjuvant RAI. RESULTS: Among the 103 patients, therapeutic CCND was performed in 17 (17 %) and prophylactic CCND in 49 (48 %). Of the 49 patients, 20 (41 %) had positive cervical lymph nodes. Positive lymph nodes changed American Joint Committee on Cancer tumor, node, metastasis staging in 17 patients and recommendations for RAI in 14. At a median follow-up of 21 months, there was no difference in Tg level based on the application of CCND; however, 92 % of patients with M0 disease had an undetectable Tg. One patient had recurrent DTC based on serum Tg only. CONCLUSIONS: Prophylactic CCND resulted in detection of unsuspected metastatic lymphadenopathy in 20 (41 %) of 49 patients and changed RAI recommendations in 14 (33 %). To date, most patients have an undetectable Tg. Longer follow-up is needed to detect potential differences in recurrent disease based on the use of CCND or long-term effects of RAI.